From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Mon, 15 Mar 1999 18:05:03 GMT Message-Id: <199903151805.SAA01926@dax.scot.redhat.com> From: "Stephen C. Tweedie" MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Subject: Re: MM question In-Reply-To: References: Sender: owner-linux-mm@kvack.org To: Magnus Ahltorp Cc: "Benjamin C.R. LaHaise" , linux-mm@kvack.org, Stephen Tweedie List-ID: Hi, On 22 Feb 1999 22:13:09 +0100, Magnus Ahltorp said: > Right now, an Arla inode has some extra information, containing a > dentry for the cache file. The readpage() function just validates the > cache information, fills in a struct file (with the ext2 inode) and > calls ext2's readpage(). The struct page pointer is passed along to > ext2's readpage() without any modifications. This sounds like the source of the problem: the Arla inode's readpage function will not be called if the page cache for the Arla page is already present. If you write to the underlying file, it will update any ext2fs page cache present for the page, but will not touch the Arla page itself. You need to call update_vm_cache() against the appropriate Arla inode for that to happen. (Ext2 will already call update_vm_cache() for the ext2fs inode, so the ext2 page cache will remain consistent internally.) Of course, you really want to take a step back at this point and work out if this is really the best way forward, since you just end up caching things twice if you are not careful... --Stephen -- To unsubscribe, send a message with 'unsubscribe linux-mm my@address' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://humbolt.geo.uu.nl/Linux-MM/